One common method to map a three dimensional area is to divide the area to be mapped into imaginary contours of equal elevation and to store the data for these contours. This is typically referred to as a “topographical” map. To achieve a desired accuracy, equal elevation contours are measured with a step size which is proportional to the required accuracy. This is an exact method of mapping, however it is not easily software related for graphic interface as it requires expensive memory for the large amount of data to be stored or the software runs very slowly.
For golf courses and the like, mapping and the use of the map with graphic interface software is well known. Such software typically has a map or graphical view of some area, such as the golf course as a whole and/or specific holes of the golf course. A graphical interface is typically provided on each golf cart, as well as a central location for monitoring of the whole course. On each golf cart is a sensor which senses location thereof, such that the interface typically provides not only a depiction of the present hole but a distance to the pin or center of the green from the golf cart. However, when a player must leave the golf cart (e.g., where the golf cart must stay on the cart path), the distance measurement given will not necessarily (and typically will not) be the same as the distance from the golf ball to the pin or center of the hole. In addition, such systems are GPS based, so that if there is any problem with the GPS or with GPS reception, such systems are rendered inoperative until the problem is corrected.
In U.S. Pat. No. 6,236,940 (Rudow et al.) and U.S. Pat. No. 6,263,279 (Bianco et al.), a “vector-based map storage scheme” is described which is based on global positioning coordinates. According to these methods, the perimeters of the important features of the hole are mapped (possibly using least square fittings to reduce the number of coordinates needed), so that a vector list is ultimately compiled to describe each feature as a flat outline of an area. When displayed, colors are used for certain feature areas, such as a sand color for sand traps and green for a putting surface (green). No use is made of any elevation data for the features.
While such prior art methods for schemes have proven useful, there is still a need to provide the mapping data in an easily used format as well as to provide elevation data in a useful manner, all of which must be consistent with the data storage limitations and software application run times.